Overview This is the last release before the announced license change (see #2973 pull request), and we are moving to GitLab! GitHub has served us well in the past years but we would like to employ the more powerful feature set of GitLab. See the announcement for more details. Features Process' changes LiquidFlow move porosity/storage from MPL solid phase to medium scale. #2872 Reactive transport process: enrich Phreeqc interface using direct memory access approach for equilibrium-controlled reactions. #2883 Rename Groundwater flow to SteadyStateDiffusion. #2860 ThermoHydroMechanics now accepts linear shape functions for displacement. #2885 Output intgration point data in RichardsMechanics process for proper restart option. #2911 RichardsMechanics now uses the alternative mass balance formulation. #2914, #2921 Computation of all secondary variables for output and restart in RichardsMechanics process is now consistent with the latest solution. #2936 RichardsMechanics now relies on the solid's bulk modulus and Biot coefficient to compute grain compressibility. #2955 Numerics Add bulk element mappings for triangles. #2901 Add mapping from points of a pyramid face to points in the pyramid element. #2913 Remove unused time discretization schemes. Only backward Euler is being used now. This simplifies certain upcoming refactorings. #2908 Input and output Fixed bug of fixed time output not being written in case of repeated time step. #3000 Material models New MPL property: CurveProperty. #2857 van Genuchten capillary pressure model. #2919 Regularized van Genuchten capillary pressure model. #2959 PermeabilityMohrCoulombFailureIndexModel. #2989 Added back names of properties for better error messages. #2958 Store properties' definition scale for each property. #2958 Improve error handling in MPL when accessing a property of wrong type. #2941 Add computation of bulk modulus for MFront solid material models. #2955 Add solid pressure. Used by RichardsMechanics for solid density update. #2999 Generalize exponential property, which now has an additive offset. #3008 File I/O Write PVD files for each subdomain output. #2949. Testing and documentation Refactored FileTools.cpp to use std::filesystem. #2918 Added documentation on how to use windows subsystem for linux (WSL). #2946 Test definitions in the project files now support regular expressions. #2945 New tools Tool to convert PVTU-meshes into regular, non-partishioned meshes and remove ghost information. #2876 Add prism element type to structured mesh generator tool. #2903 Create regular mesh consisting of pyramid elements. #2909 Correct reordering for pyramid elements in NodeReorder tool. #2937 Data Explorer Adding an array to a 2D mesh based on a raster file is now possible. #2984 Infrastructure Serial container image is built with Python enabled. #2765 Added CMake-function ogs_add_library() as a drop-in replacement for the add_library()-function. #2881 Bumped minimum compiler and use std::filesystem for temporary file creation. #2827 Replace logog logger with a modern and type safe spdlog logger. It also includes the formatting library fmt, which is a great alternative to the iostreams. #2875, #2873, #2891, #2882 Add GMRES restart to linear solver options. #2910 More flexible algorithm to specify the file names of the output in the project file. #2927 Now x_dot and dt are being passed to the computeSecondaryVariables() function allowing rate dependent secondary variable evaluation. #2935 The order of postTimeStep() and computeSecondaryVariables() has been changed, s.t. all quantities computed in the secondary variables computation are available before the post time-step call. #2936 Added GitLab CI config. #2968 CMake options changes Removed option OGS_USE_PCH, added option OGS_USE_UNITY_BUILDS to speed up compilation by using Unity builds. #2906 Version info New compiler minima (#2827): gcc: 9.0, see also #3006 clang: 9 msvc: 2019